Related papers: Nesting-induced Local Electronic Patterns around a…
Bulk FeSe is a special iron-based material in which superconductivity emerges inside a well-developed nematic phase. We present a microscopic model for this nematic superconducting state, which takes into account the mixing between $s-$wave…
We study the spin resonance in superconducting state of iron-based materials within multiband models with two unequal gaps, $\Delta_L$ and $\Delta_S$, on different Fermi surface pockets. We show that due to the indirect nature of the gap…
We study the effects of hybridization between the two electron pockets in Fe-based superconductors with s-wave gap with accidental nodes. We argue that hybridization reconstructs the Fermi surfaces and also induces an additional…
We performed an angle-resolved photoemission spectroscopy study of the Ni-based superconductor SrNi$_2$As$_2$. Electron and hole Fermi surface pockets are observed, but their different shapes and sizes lead to very poor nesting conditions.…
The discovery of high-transition temperature (high-Tc) superconductivity near antiferromagnetism in iron arsenides raised the possibility of an unconventional superconducting mechansim1-8. The observation of clear Fermi surfaces and…
We study the electronic structure within a system of phase-decoupled one-dimensional superconductors coexisting with stripe spin and charge density wave order. This system has a nodal Fermi surface (Fermi arc) in the form of a hole pocket…
The non-trivial topology in the layered $\text{FeTe}_{0.55}\text{Se}_{0.45}$ (FTS) superconductor has been suggested by both theory and experiment to be strongly dependent on the Te concentration. Motivated by this together with the Te…
To clarify the origin of the pseudogap and strange metal states as well as their mutual relationship in cuprate superconductors, a comprehensive study on the spectral function, Fermi surface, resistivity and dynamical spin susceptivity of…
The particular shape of the Fermi surface can give rise to a number of collective quantum phenomena in solids, such as density wave orderings or even superconductivity. In many new iron superconductors this shape, the 'nested' Fermi…
The role of nematic order for the mechanism of high-temperature superconductivity is highly debated. In most iron-based superconductors (IBS) the tetragonal symmetry is broken already in the normal state, resulting in orthorhombic lattice…
We use scanning tunneling spectroscopy to investigate the filled and empty electronic states of superconducting single-unit-cell FeSe deposited on SrTiO$_3$(001). We map the momentum-space band structure by combining quasiparticle…
We report on inelastic neutron scattering measurements that find incommensurate itinerant like magnetic excitations in the normal state of superconducting FeTe$_{0.6}$Se$_{0.4}$ (\Tc=14K) at wave-vector…
To understand newly discovered superconductivity in Fe--based systems, we investigate electronic structure and magnetic properties of Fe$_{1+x}$Te using first--principles density functional calculations. While the undoped FeTe has the same…
Strong correlations lead to emergent excitations at low energies. When combined with symmetry constraints, they may produce topological electronic states near the Fermi energy. Within this general framework, here we address the topological…
The origin of the high temperature superconductivity in the iron-based superconductors remains elusive after being extensively studied for more than a decade. Determination of the pairing symmetry is essential in understanding the…
We use angle resolved photoemission spectroscopy (ARPES) to study the band structure of BaFe2As2 and CaFe2As2, two of the parent compounds of the iron arsenic high temperature superconductors. We find clear evidence for band back folding…
Topological superconductors should be able to provide essential ingredients for quantum computing, but are very challenging to realize. Spin-orbit interaction in iron-based superconductors opens the energy gap between the $p$-states of…
Elucidating the relationship between spin excitations and fermiology is essential for clarifying the pairing mechanism in iron-based superconductors (FeSCs). Here, we report inelastic neutron scattering results on the hole overdoped…
The emergence of nematic electronic states accompanied by a structural phase transition is a recurring theme in many correlated electron materials, including the high-temperature copper oxide- and iron-based superconductors. We provide…
Topological insulators and semimetals as well as unconventional iron-based superconductors have attracted major recent attention in condensed matter physics. Previously, however, little overlap has been identified between these two vibrant…